Method of and apparatus for dehydrating petroleum oil



' Oct. 28, 1930. H. c. EDDY I 1,779,695

METHOD OF AND APPARATUS FOR DEHYDRATING PETROLEUM OIL Original Filed Aug; 4, 1926 INCE'NTOR; #419040 6, 500x,

"HTTQRA Ex Patented Oct- 28, 1930 UNITED STATES PATENT OFFICE IH.'AROLD c. EDDY, or Los ANGELES, CALIFORNIA, AssIsNoa'ro PETROLEUM :a criJs-Y- me comm or camomwm, or LOS ANGELES, CALIFORNIA, A conrorwrron or CALIFORNIA METHOD OF AND APPARATUS FOR DEHYDRATING PETROLEUM OIL Application filed August 4, 1926, Serial 110.4%,972. Renewed September 1, 1928.

My invention relates to a novel form of electrical dehydrator adapted for use in deemulsifying petroleum oil.

Petroleum oil as it is taken from a well 5 carries particles of trapped water which can be removed therefrom only by a special process. Electrical dehydrators are used extensivcly for the purpose of de-emulsifying .the petroleum oil. A common form of electrical m dehydrator consists of a tank in which a pair of electrodes of difl'erent polarity is placed. These electrodes are included in an electrical circuit so that a high potential electric field may be set up in the space be tween them. The emulsified oil is passed through the electric field andthe small particles of water are caused to coalesce by the action of the electric field, forming globules of water which are of suflicient size to separate from the oil by gravity.

'I have found that the de-emulsifying of the oil may be facilitated by mixing the emulsified oil with the oil which has been previously treated, and then passing this mixture through the electric field.

It is .an object of this invention to pro vide an electrical dehydrator in which the emulsified oil is mixed with a treated or deemulsified oil just before it is passed through the electric field of the dehydrator.

Other objectsignand advantages of the invention will be ade evident hereinafter.

Referring to the drawing in which I illustrate the invention,

hydrator in which the features of my invention are incorporated.

Fig. 2 is a section taken on the line 2"2 of Fig. '1. L

Fig. 3 is a fragmentary section of the upper end of Fig. 1, being taken at right angles thereto.

Figs. 4 and 5 are enlarged fragmentary sec- Fig. 1 is a vertical section through a deleg 21 which extends through an opening 22- in the lower part of the tube 17 to the interior thereof.

Supported above the grounded electrode 13 isa live electrode 25. The live electrode 25 has a frusto-conical member 26 which, as il- I lustrated in Fig. 1, is of shar er taper than the grounded electrode 13. ecured to the frusto-conical member 26 'is-a plurality of concentric rings'27. There is a treating space 29 provided between the electrodes 25 and 13. It should be noted that near the central part of the treating space 29 the distance between the electrodes. 26 and 13 is much greater than the distance between these electrodes at the extremities of the treating space 29. i The live electrode 25 is provided with straps 30'which are attached to the frustoan upper shaft 31. The upper shaft 31is at tached to, an'insu-lator 33 .which is supported at the lower end of a hanger rod 35. The hanger rod-extends upward through a bearing 36 and the upper end thereof is attached .to a link 37, which is attached to a crank pin 38 of acrank 39. The crank 39 has a shaft 40 which is rotatably supported by a bearing 41 attached to the upper part of the tank 11.

Secured in the top of the tank 11 is an in-- sulator. bushing42 to which a wire 4 is attached. The wire 43 is also attached to the live electrode 25 by means of-which electrical energy is supplied thereto.

Referring in particular to Figs. 2-, 4 and 5, the central part of the frusto-conical member 26 has a short cylindrical portion 46, at the upper end of which is formed a radially exconical member 26,- these straps supporting tending annular flange 47 and a cross bar .48. A hinge-bar 50 is extendedfacross the short cylinder 46 immediately below the crossbar 48 and valve plates 51 are pivoted thereto,

' structed.

These resiliently mounted valve plates 51 thus comprise a one-way valve means which admits dry treated oil to the treating Space, but prevents any reverse flow.

The operation of. the invention is substantially as follows:

. The emulsion which consists of oil and water is introduced into the tank 11 by the pipe 20. This emulsion passes into the tube 17, flowing upward into the treating space 29.-

The grounded and live electrodes 13 and 25,

according to standard dehydrator practice,

are included in a high potential electrical circuit, the tank being grounded and the bushing 42 having a conductor connected thereto so that a high potential electric field is set up in the treating space 29. The emulsion passes outward through the treating space 29 and the particles of trapped water are coalesced into globules of water which have suflicient weight to separate from the emulsion by gravity. As the emulsion is treated, it is gradually freed of its water content, the water content'falling to the bottom of the chamber 11, forming a body .as indicated by the numeral55. The water may be withdrawn from the chamber 11 by means of a water outlet pipe 56. The treated oil passes to the upper part of the chamber 12 and may be withdrawn therefrom through an outlet oil pipe 57. A small portion of the oil which passes from. the treating space 29 is carried through the annular openin 15 to the space above the body of water 55 ut immediately below the grounded electrode 13. When the emulsion passes into the. central part of the treating space 29, its water content is quite highandits dielectric properties are comparatively low as compared with the dielectric propertiesof the .oil as'it passes from the extremity of the treating space 29. To compensate for this gradual increase in dielectric properties which occur as the emulsion passes outward, the electrodes 13 and 25 are so formed that the distance'therebetween decreases as the outer portions of the treatin space is reached. I

en'the dehydrator is in o eration the crank 39 is operated so thatthe live electrode '25 is reciprocated from the position shown in full lines in Fig. 1 into the position shown by dottedlines 58 of Fig; 1. It is well known .that the globules of water tend to form in short-circuiting chains between the ciprocating the live. electrode'25 is to op erate the valve plates 51. During the up stroke of the live electrode 25 the valve plates 51 are moved from the position shown in Figs; 1 and 4 into the positions shown in Fig. 5 and by dotted lines 59 in Fig. 1. When the live electrode is moved upward, the treating space 29 is enlarged and oil which has been de-emulsified or already treated in the treating space 29 is drawn through the openings 52 into the central part of the trating space 29. The treated oil is at this point mixed with the emulsion passing upward through the tube 17, this mixture pass ing outward through the treating space 29.

The purpose of mixing treated oil with the emulsion in its passage through the treating space29 is to maintain the fluid at a high dielectric strength so as to prevent the pas- ;sage of disruptive discharges through the body of oil or emulsion, thus allowing a high voltage to be maintained between the electrodes -without appreciable .current flow. During the down stroke of the live electrode 25 the treating space 29 is decreased and the mixture being treated is forced outward therethrough. I have found that by mixing emulsion with a treated oil, very successful results may be obtained both from an eflicien'cy and economical standpoint. The reciprocation of the live electrodes 25 provides a circulation of treated oil which is mixed with the inflowing emulsion continuously during the operation of the dehydrator. The oil which has dropped through the annular opening 15 is drawn through the openings 19 into the upper end of the tube 17 and is mixed with the emulsion and the treated oil which has been drawn through the openings 52.

From the foregoing description it is apparent that my invention provides a very simple means for mixlng treated oil and untreated emulsion together immediately before it passes through the treating space. This is the foremost feature of the invention.

I claim as my invention: 1. An electrical dehydrator comprising: a tank; a grounded electrode mounted in said tank; a live electrode supported above said grounded electrode, there being a treating spacebetween said electrodes; means for introducingemulsion into said treating space; a valve carriedby said live electrode; means for operating said valve so as to introduce treated oil into said treating space to be mixed with said emulsion; oil outlet means for said tank; and water outlet means for said tank.

2. An electrical dehydrator comprising: a tank; a grounded electrode mounted in said tank; a live electrode supported above said space between said electrodes; a tube extending downward from said grounded electrode, said tube connecting to said treating space; means'for introducing emulsion into said tube, said emulsion flowing into sa d treating space; a valve carried by said live electrode; means for operating said valve so as to introduce treated oil into said treating space to be mixed. with said emulsion; oil outlet meansfor said tank; and water outlet means for said tank.

4. An electrical dehydrator comprising: a

" tank; a grounded electrode mounted in said said grounded electrode,

tank; a live electrode supported grounded electrode, there being a treating space between said electrodes; a tube extending downward from said grounded electrode, said tube connecting to said treating space; means for introducing emulsion into said tube. said emulsidn flowing into sa d treating space; a valve carried by said l ve electrode ;means for reciprocating said llve electrode, thus operating said'valve so as to 1ntroduceftreated oil into said treating space to be mixed with said emulsion; oil outlet means for said tank; and-water outlet means for said tank. j

5. An electrical dehydrator compr1s1ng: a tank; a grounded electrode mounted m'said tank, there being grounded electrode; a live electrode supported above said grounded electrode, there being a treating space between said elec-' trodes; a tube extending downward from saidtube connecting to said treating space, opening formed at the upper end of said tube through through said space around said grounded electrode may pass into said treating space;

' means for introducing emulsion into said tube, said emulsion flowing into said treating space; a valve carried by said live electrode; means for operating said valve so as to introduce treated oil into said treating space to be mixed with said emulsion; oil

. thus operating said valve so as tointroduce above said for admitting treated oil into said treating a space around saidthere; being an which treated oil which has fallen trode, said tube connecting to said treating 7 space, there being an opening formed at the upperend of said tube through which treated oil which has fallen through said space around said space around said grounded electrode may pass into said treating space; means for introducing emulsion. into said tube, said emulsion flowing into said treating space; a valve carried by said live electrode;

means for reciprocating said live electrode,

treatedi oil into .said treating space to be mixed with 'said emulsion; oil outlet means for Isaid tank; and water outlet means for said tan 1 7 In a dehydrator, the combination of:

a pair of spaced electrodes providing a treat ing space therebetween; means for introducing an emulsion into said treating space; and valve means in,one of said electrodes for admitting treated oil directly into said treating space. 5

8. In a dehydrator, the combination of: a pair of spaced electrodes providing a treating space therebetween; means for introducing an emulsion into said treating space; and valve means operated by a deciprocation of one of said electrodes for admitting treated oil into said treating space.

9. In a dehydrator, the combination of: a pair of spaced electrodes providing a treating space therebetween; means for introducing an emulsion into-said treating space; and check valve means in one of said electrodes space but preventing any reverseflow.

In a' dehydrator, the combination of: a pair of spaced electrodes providing a treating space therebetween; means communicating between said treating space and a body of treated oil; and fluid-operated valve means in said. last-mentioned means for admitting treated oil into said treatin space.

In testimony whereof,.I ave hereunto set my hand at Los Angeles, California, this 30th day of July, 1926. v e HAROLD C. EDDY; 

